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750/760 Feeder Management Relay GE Power Management
17.9 CONTROL SCHEMES 17 COMMISSIONING
17
17.9.3 MANUAL CLOSE FEATURE BLOCKING
Make connections per Figure 17–1: RELAY TEST WIRING – WYE CONNECTION or Figure 17–2: RELAY
TEST WIRING – DELTA CONNECTION on page 17–4.
Function and Timer Control:
Assert the 52a (or 52b) Contact logic input to simulate an open breaker.
1. If in Local mode, press the front panel CLOSE key momentarily to generate a close command; if in Remote
mode assert a momentary Remote Close logic input to cause the relay to go into manual close blocking,
and generate an output from this feature. Check that any selected output relays have operated. If the func-
tion is selected as Alarm, the alarm message should be displayed with the ALARM LED turned on.
2. After a time interval equal to the Manual Close Block Time, the above indications should reset. This inter-
val can be checked in the Event Recorder.
a) CONTROL OF O/C PROTECTION FEATURES
Phase Inst OC 1 Blocking
1. Set a test current, in the number of phases required to generate an output, to a level above the pickup of
this element then turn the current off.
2. Apply a Close command, as described above, and immediately inject the test current to the relay. The ele-
ment will not pickup as it is blocked by manual close blocking. Wait until the element operates, as shown
by the PICKUP indicator coming on, at the end of the programmed Manual Close Block Time.
3. Turn the current off. The time interval can be checked in the Event Recorder.
Neutral Inst OC 1 Blocking
1. Follow the procedure described for Phase Inst OC 1 Blocking, injecting current as appropriate.
2. Ground Inst OC Blocking
3. Follow the procedure described for Phase Inst OC 1 Blocking, injecting current as appropriate.
Ground Inst OC Blocking
Follow the procedure described for Phase Inst OC 1 Blocking, injecting current as appropriate.
Sensitive Ground Inst OC Blocking
Follow the procedure described for Phase Inst OC 1 Blocking, injecting current as appropriate.
Neg Seq Inst OC Blocking
Follow the procedure described for Phase Inst OC 1 Blocking, injecting current as appropriate.
Phase Time OC 1 Raised Pickup
1. Ensure all other O/C features are Disabled.
2. Manual Close Blocking will raise the pickup setting of the Curve normally used by this feature the pro-
grammed percentage. Set a test current to a level between the normal pickup setting and the raised set-
ting, then turn the current off.
3. Apply a Close command, as described above, and immediately inject the test current into the relay. Phase
time O/C will not pickup as the pickup current is raised. Increase the injection current until the PICKUP
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